1. Field of the Invention
This invention relates to fluid cooled electrical inductive apparatus and, more particularly, to a pattern for spacer blocks disposed between adjacent electrical coils in the core coil assembly.
2. Description of the Prior Art
Electrical inductive apparatus, such as transformers and reactors of the shell-form type, include one or more windings, each formed of a plurality of serially connected pancake type coils. Such coils are disposed in spaced side-by-side relation, separated by insulating spacer washers. Each spacer washer includes an insulating sheet having a plurality of rectangular insulating blocks attached thereto with a suitable adhesive. When assembled the blocks are in contact with the turns of the pancake coil so that the insulating sheet washer and adjacent surface of the pancake coil provide a cooling duct through which a fluid cooling dielectric, such as oil, flows. The rectangular blocks space the coil from the insulating sheet washer, they provide a plurality of paths through which the fluid coolant flows, and they support the turns of the pancake coil to prevent them from being deformed due to short circuit forces. The placement and gluing of the rectangular blocks on the insulating sheet washer is time consuming and costly.
Another disadvantage of prior procedures was that no reference point was used for insuring exact alignment of all spacers on all washers within a phase regardless of washer size and washer offset.